Reference

perltex(1) on Linux

The text 4d3d5b682c8c, as Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie), Debian 7 (Wheezy) shipped it.

enable LaTeX macros to be defined in terms of Perl code

Flags it lists

perltex(1) on Linux now